1. Field of the Invention
The present invention relates to a gamut compression method, a gamut compression device, and a program for performing appropriate color reproduction between different types of devices or between different types of media for use in a color management system.
2. Description of the Related Art
To reproduce color among different types of devices and different types of media, a difference in gamut between input and output devices needs to be corrected. The technique for this process is referred to as a color gamut compression. For example, there are a variety of types of display output devices including a cathode ray tube (CRT), a projector, and a liquid-crystal panel. The projectors include various subtypes such as DLP projector and SXRD projector, and the liquid-crystal panels include a subtype such as LED backlight panel. These types have different color gamuts thereof.
For example, FIG. 20 illustrates difference in the color gamut of a variety of display output devices, device A through device E, as XYZ color diagrams.
The reproducible color gamut is different from device to device. When a video signal is displayed on a given display output device, the video signal needs to be corrected in accordance with the display output device.
To correct difference in gamut, in widely accepted practice, signal values unique to device and media, such as R, G and B values, are converted into a device-independent display color system such as L*a*b color space standardized by Commission Internationale de I'Ecalairage (CIE), and compression is performed on the device-independent color system.